Putting the Pacific marine heatwave into perspective: The response of larval fish off southern California to unprecedented warming in 2014–2016 relative to the previous 65 years

2021 ◽  
Author(s):  
Andrew R. Thompson ◽  
Noah J. Ben‐Aderet ◽  
Noelle M. Bowlin ◽  
Dovi Kacev ◽  
Rasmus Swalethorp ◽  
...  
Keyword(s):  
Southern California ◽  
Larval Fish ◽  
The Pacific

Waste Disposal in the Sea off Southern California

1986 ◽  
Vol 18 (11) ◽  
pp. 1-9 ◽  
Author(s):  
Willard Bascom
Keyword(s):  
Waste Water ◽  
Coastal Waters ◽  
Southern California ◽  
State Standards ◽  
Waste Streams ◽  
Cool Water ◽  
Water Research ◽  
The Pacific ◽  
Steady Improvement ◽  
Deep Cool

Southern California, with a coastal population of 12 million people, releases about 4.4 million cubic meters of treated waste water into the Pacific every day via outfalls that discharge three to six kilometers offshore at a depth of 60 meters. Diffusers cause each liter of waste to be diluted by 150 liters of deep cool water preventing it from reaching the surface except for short periods in winter. Data on the constituents of the four largest waste streams are presented and a brief account of the research done by the Southern California Coastal Water Research Project is given. Although the waste water now discharged meets rigorous state standards (with minor exceptions) and the steady improvement in sea conditions over a decade has been well documented, there is a continuing debate over whether our coastal waters are adequately protected. This is primarily because the damaging effects of DDT and PCBs that were discharged more than 14 years ago have been slow to go away. Although the amounts of DDT and PCB in sea animals are only one- tenth what they were a decade ago they tend to obscure the value of the improvements and the present discharge practices. The alternatives to sea disposal seem likely to cause greater damage to the overall environment.

scholarly journals A revised position for the primary strand of the Pleistocene-Holocene San Andreas fault in southern California

2021 ◽  
Vol 7 (13) ◽  
pp. eaaz5691
Author(s):  
Kimberly Blisniuk ◽  
Katherine Scharer ◽  
Warren D. Sharp ◽  
Roland Burgmann ◽  
Colin Amos ◽  
...  
Keyword(s):  
Los Angeles ◽  
Southern California ◽  
San Andreas Fault ◽  
Slip Rate ◽  
Large Magnitude ◽  
Slip Rates ◽  
San Andreas ◽  
The Pacific ◽  
Large Earthquakes ◽  
Dependent Probability

The San Andreas fault has the highest calculated time-dependent probability for large-magnitude earthquakes in southern California. However, where the fault is multistranded east of the Los Angeles metropolitan area, it has been uncertain which strand has the fastest slip rate and, therefore, which has the highest probability of a destructive earthquake. Reconstruction of offset Pleistocene-Holocene landforms dated using the uranium-thorium soil carbonate and beryllium-10 surface exposure techniques indicates slip rates of 24.1 ± 3 millimeter per year for the San Andreas fault, with 21.6 ± 2 and 2.5 ± 1 millimeters per year for the Mission Creek and Banning strands, respectively. These data establish the Mission Creek strand as the primary fault bounding the Pacific and North American plates at this latitude and imply that 6 to 9 meters of elastic strain has accumulated along the fault since the most recent surface-rupturing earthquake, highlighting the potential for large earthquakes along this strand.

A multidisciplinary approach to seismic hazard in southern California

1994 ◽  
Vol 84 (5) ◽  
pp. 1293-1309
Author(s):  
Steven N. Ward
Keyword(s):  
Seismic Hazard ◽  
Southern California ◽  
Current Model ◽  
Seismic Hazard Assessment ◽  
Historical Seismicity ◽  
San Andreas ◽  
The Pacific ◽  
Moderate Earthquake ◽  
Earthquake Potential ◽  
Seismic Moment Release

Abstract A serious obstacle facing seismic hazard assessment in southern California has been the characterization of earthquake potential in areas far from known major faults where historical seismicity and paleoseismic data are sparse. This article attempts to fill the voids in earthquake statistics by generating “master model” maps of seismic hazard that blend information from geology, paleoseismology, space geodesy, observational seismology, and synthetic seismicity. The current model suggests that about 40% of the seismic moment release in southern California could occur in widely scattered areas away from the principal faults. As a result, over a 30-yr period, nearly all of the region from the Pacific Ocean to 50 km east of the San Andreas Fault has a greater than 50/50 chance of experiencing moderate shaking of 0.1 g or greater, and about a 1 in 20 chance of suffering levels exceeding 0.3 g. For most of the residents of southern California, thelion's share of hazard from moderate earthquake shaking over a 30-yr period derives from smaller, closer, more frequent earthquakes in the magnitude range (5 ≦ M ≦ 7) rather than from large San Andreas ruptures, whatever their likelihood.

scholarly journals Five-century record of climate and groundwater recharge variability in southern California

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
F. Manna ◽  
K. M. Walton ◽  
J. A. Cherry ◽  
B. L. Parker
Keyword(s):  
Los Angeles ◽  
Groundwater Recharge ◽  
Southern California ◽  
Surface Soil ◽  
Time Interval ◽  
Chloride Salt ◽  
Freshwater Flow ◽  
The Pacific ◽  
Salt Distribution

AbstractModifications to the rates of water flowing from the surface to groundwater (groundwater recharge) due to climate variability are the most difficult to assess because of the lack of direct long-term observations. Here, we analyze the chloride salt distribution below the surface soil on a plateau near Los Angeles to reconstruct the amount of recharge that occurred in the last five centuries. Over this time interval, periods of major high and low recharge with different duration follow each other and this cyclicity is consistent with long-term atmospheric forcing patterns, such as the Pacific Decadal Oscillation. This study determines the range and the natural variability of recharge to groundwater, which sustains local freshwater flow system, and helps forecast future availability of groundwater resource in southern California, where water scarcity is critical to both local and global populations.

Speocarcinus berglundi n. sp. (Decapoda: Brachyura), a new crab from the Imperial Formation (late Miocene-late Pliocene) of southern California

1994 ◽  
Vol 68 (4) ◽  
pp. 800-807 ◽  
Author(s):  
Annette B. Tucker ◽  
Rodney M. Feldmann ◽  
Charles L. Powell
Keyword(s):  
New Species ◽  
Late Miocene ◽  
Southern California ◽  
Late Pliocene ◽  
Riverside County ◽  
Isthmus Of Panama ◽  
The Pacific ◽  
Extant Species ◽  
The Caribbean ◽  
A New Species

Speocarcinus berglundi n. sp. is described from the Imperial Formation in Riverside County, California. Although the Imperial Formation spans late Miocene through late Pliocene time, the part of the unit that bears crabs has been radiometrically dated as late Miocene. The identification of a new species was based upon comparison with four extant species and represents the first documented fossil occurrence for the genus. The occurrence of this new species suggests that the genus may have originated in the Pacific and, during the Miocene, dispersed through the Isthmus of Panama to the Caribbean. Two of the specimens exhibit parasitism by Bopyridae (Isopoda).

Sign in / Sign up

Export Citation Format

Share Document